Method and apparatus for removing screen wire members from multi-level screen deck assemblies

ABSTRACT

The screen wire members are removed by first loosening the nuts on the clamp bar holding bolts and then moving the bolts axially inwardly to thereby move the clamp bars to a non-holding position. This is accomplished by the use of a plurality of clamp bar tools which are fastened to the ends of pairs of vertically spaced bolts, the lower of which is at the level where the screen wire member is to be removed and the upper of which is at the next higher level of the multi-screen deck assembly.

United States Patent 1 n l r 3,718,963 Hawkins et al. I4 March 6, 1973METHOD AND APPARATUS FOR 3,617,083 ll/l97l Koppensteiner ..29/278REMOVING SCREEN WIRE MEMBERS 1,713,144 5/ 1929 FROM MULTI-LEVEL SCREENDECK 2,630,225 3/1953 ASSEMBLIES 2,772,440 12/1956 2,274,700 3/ l 942{76] Inventors: George C. Hawkins, 9636 North 2,599,434 6/1952 RiversideDrive, Mequon, Wis. 14 10/1967 53092; James H. Cutts, 5450 North 337433/1968 Long Island Drive Milwaukee Wis 3666277 5/1972 5 0 r 2,975,9003/1961 Hoffman ..209/403 [22] Fil d; N 25, 1970 Primary Examiner-CharlesW. Lanham Assistant Examiner-D. C. Crane [21] Appl' 92763 Attorney-JohnW. Michael, Gerrit D. Foster, Bayard H. Michael, Paul R. Puemer, JosephA. Gemignani, 521 U.S.Cl. ..29/200 0, 29/200 H, 29/270, Robert Clemency,Andrew 0- R r l n A- 209/405 209 03 Buse and Spencer B. Michael [51]Int. Cl. ..B23p 19/00 [581 Field of Search ..29/2075 SL, 270, [571ABSTRACT 207-5 29/2075 207-5 The screen wire members are removed byfirst loosen- QD 200 203 270; 209/233, ing the nuts on the clamp barholding bolts and then 410, 14 4034053 moving the bolts axially inwardlyto thereby move the 16/114 R, Q R clamp bars to a non-holding position.This is accomplished by the use of a plurality of clamp bar tools [56]References C'ted which are fastened to the ends of pairs of verticallyUNITED STATES PATENTS spaced bolts, the lower of which is at the levelwhere the screen wire member is to be removed and the 2,131,687 9/ 1938Kaplan ..29/278 upper of which is at the next higher level of the multi-2,770,032 1 H1956 Kelly ..29/270 screen deck assemb]y 3,137,065 6/1964Harris ..29/278 3,583,744 6/1971 Paine ..29/278 4 Claims, 3 DrawingFigures METHOD AND APPARATUS FOR REMOVING SCREEN WIRE MEMBERS FROMMULTI-LEVEL SCREEN DECK ASSEMBLIES BACKGROUND OF INVENTION a minimum ofmodification to existing structures for its use.

SUMMARY OF INVENTION The method of this invention relates to the removalof a screen wire member from a multi-level screen deck assembly in whicheach of the screen wire members are held in place by a holding assemblyincluding a pair of clamp bars and a plurality of bolts extendingthrough each clamp bar in the side of the screen box with the boltshaving a holding and a locking nut threaded on the external ends thereofto clamp the parts in operating position.

The steps of the method include removal of the lock nuts from four boltsat the level at which it is desired to remove a screen wire member withthe nuts being removed from two bolts in one clamp bar and from twobolts in the other clamp bar. Next, the lock nuts are removed from fourbolts at the next highest level, said nuts being removed from the boltslocated directly above the bolts referred to above. The next step is toloosen all remaining lock nuts and all holding nuts about 2 inches onthe bolts in the clamp bars holding the screen wire member in place.Next, an inward axial movement is imparted to the bolts from which thelock nuts have been removed which, in turn, provides an inward andupward movement to the clamp bars to thereby move them to a non-holdingposition. This step is facilitated by the use of a clamp bar tool havingpairs of vertically spaced openings which are adapted to fit over theends of the vertically spaced bolts from which the lock nuts have beenremoved. Axial movement to the lower bolts is provided by reinstallingthe lock nuts over the ends of the clamp bar tool and tightening themsnugly in place. The final step is simply to remove the screen wiremember out from under the clamp bars which have been moved to anon-holding position.

DESCRIPTION OF DRAWINGS FIG. 1 is a fragmentary end elevation view of atypical multi-screen deck assembly of the type the present invention isdesigned to be used with;

FIG. 2 is an enlarged fragmentary end elevation view showing the screenwire removal tool of the present invention in its operative position;and

FIG. 3 is a view taken along line 3-3 of FIG. 1 with certain partsbroken away.

2 DESCRIPTION OF PREFERRED EMBODIMENT Referring now to the drawings indetail, FIG. 1 shows a typical multi-screen deck assembly of the typewith which the present invention is designed to be used. Such assemblyis comprised of a screen box 10 in which a plurality of screen wiresupport assemblies are mounted. The number of such screen wire supportassemblies in any particular unit will vary. In the structure shown inFIG. 1 there are three such assemblies labeled A, B and C.

Each screen wire support assembly or deck is comprised of a pair ofoppositely facing elongated support bars 12,12 fastened to the insidewall of the screen box by welding or other suitable means. Supported onsupport bars 12,12 are screen frame members 14 on top of which aresupported a sub-screen member 16 which in turn supports a screen wiremember 18.

Each of screen wire assemblies: A, B and C are held securely in place bya pair of elongated clamp bars 20, 20. The clamp bars are mounted on aplurality of carriage bolts 22 which in turn are mounted in and extendthrough a plurality of clamp lugs 24 welded or otherwise fastened to theouter surface of the screen box. As most clearly shown in FIG. 2, lugs24 are mounted at openings 25 in the sides of screen box 10 so thatbolts 22 will extend from the interior to the exterior of the screenbox. Threaded on each carriage bolt 22 are pairs of holding and lockingnuts 26 and. 28, respectively. For reasons which will be explained indetail hereinafter, axial movement of bolts 22 with respect to clampbars 20 is restrained by any suitable means such as a washer 30 weldedor otherwise fastened to each bolt. Also as best shown in FIG. 2, screenwire members 18 have small upwardly extending lips 19 which cooperatewith lips 21 on clamp bars 20 to securely hold the parts in operatingposition.

As shown in FIG. 3, each deck assembly A, B and C includes a pair ofscreen wire members 18 positioned end to end with each of the two screenwire members being secured in operative position by a pair of clamp bars20. Thus, at each deck level there are two screen wire members 18 andfour clamp bars 20. For purposes of explanation the two screen wiremembers 18, as shown in FIG. 3, are labeled FRONT and REAR. Also asshown in FIG. 2, the present invention contemplates the use of a clampbar tool 32 which is made of substantially rigid material such as steel.Tool 32 is shaped somewhat like a question mark and is provided withspaced openings 34 and 36 for purposes to be described in detailhereinafter. Tool 32 is comprised of upper and lower clamping faces 38and 40 rigidly connected together by a bar member 42 formed integrallywith face portions 38 and 40. Opening 34 is located in face portion 40and opening 36 is located in face portion 38. The planes of faceportions 40 and 38 extend substantially parallel with each other. Faceportion 38 is provided with a bar-like extension 44 formed integrallytherewith which serves primarily as a handle for manipulation of theclamp bar tool.

As indicated previously, the above described structure is designed forscreening of aggregate material wherein the material is deposited fromthe top onto deck A and is subsequently screened from deck A to deck Band then to deck C by a vibratory action imparted to the entireassembly. The mesh of the screen wire members 18 becomes subsequentlysmaller from the top to the bottom of the unit so that the coarseraggregate is taken off at deck A, less coarse aggregate at deck B and soon down through the assembly. Since the details of the vibratory means,the screens themselves, the screen box and the aggregate handlingapparatus are not material to an explanation of the present invention,such details are not shown or described herein.

As indicated previously, this invention is specifically related to therequirement for periodic removal of the screen wire members 18 forreplacement and/or repair.

In the use of the present invention, the steps employed for removal of ascreen wire 18 are as follows. The description which follows willspecifically relate to the removal of the FRONT screen wire member 18from the deck C assembly.

I. Remove lock nuts 28 from four of the carriage bolts 22, two on eachside of FRONT screen wire member 18. While the particular carriage boltsfrom which lock nuts 28 are removed can vary somewhat, it is the usualpractice to remove nuts 28 at the four bolts located at the ends of thetwo clamp bars holding FRONT screen wire member 18. 2. Remove lock nuts28 from the four carriage bolts 28 at deck level B from the boltslocated directly above the bolts from which the nuts 28 were removed atlevel C in step (1) above. 3. Loosen all remaining lock nuts 28 and allnuts 26 about 2 inches on all bolts 22 holding the FRONT screen wiremember 18. 4. Install four clamp bar tools 32 on the ends of carriagebolts 22 at decks C and B from which lock nuts 28 have been removed insteps (1) and (2) above. As shown in FIG. 2, tools 32 are installed sothat the bolts at deck C extend through openings 34 and the bolts atdeck B extend through openings 36 in the respective tools 32. 5.Reinstall lock nuts '28 on the bolts on which clamp bar tools 32 havebeen installed and tighten them up snugly. As shown in FIG. 2, suchtightening of the lock nuts will cause the bolts 22 at deck C to beforced to move axially inwardly which in turn will cause the clamp barsat deck C to move slightly upwardly and inwardly to the position shownin FIG. 2. 6. With the parts in the FIG. 2 position, the FRONT screenwire member 18 at deck C can be easily removed by one man by simplypulling it in the direction shown by the arrow in FIG. 3. 7. After areplacement screen wire member 18 is installed, clamp bar tools areremoved and nuts 26 and 28 are tightened up to their original positions.

The rear screen wire member 18 at level C can then be replaced byfollowing the same sequence of steps as described above. After bothscreen wire members at level C have been replaced, the screen wiremembers at level B can be replaced by following the steps outlined abovebut using the screen wire tool between levels B and A. Since the screenwire members at level A are exposed from the top, they can be easilyremoved from the top by simply loosening up the nuts on the bolts atlevel A, there being no need for the special clamp bar tool 32 asutilized at levels B and C.

From the foregoing description it will be appreciated that the methodand apparatus of this invention provides a simple and inexpensivearrangement for removal and replacement of screen wire members 18. Ofparticular importance is the fact that the entire operation can beperformed by a single worker resultmg m substantial savings in laborexpense as compared with most previous methods.

We claim:

1. Apparatus for removing a screen wire member from a multi-level screendeck assembly in which each of said screen wire members is held in placeby a holding assembly including a pair of clamping bars and a pluralityof bolts extending through said clamp bars and a side of the screen box,said bolts having a holding means mounted on the external ends thereofcomprismg:

a plurality of clamp bar tools each having an upper and lower faceportion rigidly held together by a connector bar member, said upper andlower face portions each having an opening therein, said openingsadapted to receive the ends of a pair of vertically spaced clamp barholding bolts at two successive levels of said multi-level screen deckassembly; and

a restraining means to prevent axial movement of said spaced clamp barholding bolts relative to said clamp bars.

2. Apparatus according to claim 1 in which the planes of said upper andlower face portions are in substantially spaced parallel relationshipwith each other.

3. Apparatus according to claim 1 in which said face portions andconnector bar member are formed integrally with each other.

4. Apparatus according to claim 1 in which said upper face portion has ahandle member fastened thereto and extending substantially at rightangles therefrom.

1. Apparatus for removing a screen wire member from a multilevel screendeck assembly in which each of said screen wire members is held in placeby a holding assembly including a pair of clamping bars and a pluralityof bolts extending through said clamp bars and a side of the screen box,said bolts having a holding means moUnted on the external ends thereofcomprising: a plurality of clamp bar tools each having an upper andlower face portion rigidly held together by a connector bar member, saidupper and lower face portions each having an opening therein, saidopenings adapted to receive the ends of a pair of vertically spacedclamp bar holding bolts at two successive levels of said multi-levelscreen deck assembly; and a restraining means to prevent axial movementof said spaced clamp bar holding bolts relative to said clamp bars. 1.Apparatus for removing a screen wire member from a multi-level screendeck assembly in which each of said screen wire members is held in placeby a holding assembly including a pair of clamping bars and a pluralityof bolts extending through said clamp bars and a side of the screen box,said bolts having a holding means moUnted on the external ends thereofcomprising: a plurality of clamp bar tools each having an upper andlower face portion rigidly held together by a connector bar member, saidupper and lower face portions each having an opening therein, saidopenings adapted to receive the ends of a pair of vertically spacedclamp bar holding bolts at two successive levels of said multi-levelscreen deck assembly; and a restraining means to prevent axial movementof said spaced clamp bar holding bolts relative to said clamp bars. 2.Apparatus according to claim 1 in which the planes of said upper andlower face portions are in substantially spaced parallel relationshipwith each other.
 3. Apparatus according to claim 1 in which said faceportions and connector bar member are formed integrally with each other.